Abstract
BACKGROUND: Colorectal cancer (CRC) is among the leading causes of cancer-related mortality worldwide. This study aimed to assess the global burden of CRC across 204 countries and territories from 1990 to 2021, and identify its attributable risk factors. METHODS: Estimates of CRC incidence, mortality, and disability-adjusted life years (DALYs) were derived from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021, stratified by age, sex, and geographical region over the 1990-2021 period. Additionally, DALYs attributable to risk factors with established causal links to CRC were calculated. RESULTS: 100,000 population (95% uncertainty interval [UI]: 25.36-29.90), mortality rate 13.23 per 100,000 (95% UI: 12.04-14.19), and DALY rate 309.21 per 100,000 (95% UI: 287.52-331.52). The number of new CRC cases increased from 916,583 in 1990 to 2,194,143 in 2021. The age-standardized incidence rate (ASIR) rose from 24.0 to 25.6 per 100,000. High SDI (Socio-demographic Index) regions had the highest ASIR (40.5 per 100,000 in 2021), while low SDI regions had the lowest (7.4 per 100,000 in 2021). Between 1990 and 2021, the global age-standardized mortality rate (ASDR) decreased from 15.6 to 12.4 per 100,000, and the age-standardized DALY rate declined from 357.3 to 283.2 per 100,000. However, this reduction was uneven across SDI regions. Key risk factors included behavioral and metabolic factors, among which a diet low in whole grains significantly increased CRC incidence. CONCLUSION: From 1990 to 2021, the global CRC burden increased significantly, with notable variations across SDI regions. While high SDI regions made progress in reducing mortality and DALYs, low SDI regions now face a heavier burden. Targeted interventions for modifiable risk factors and improved healthcare access in less developed regions are essential to mitigate the global impact of CRC.